Releasable dovetail corner joint

Abstract

A corner leg assembly comprises two grooved mating elements divided longitudinally which when held together form the female groove portion of two dovetail joints, one on each side facing laterally 90 degrees apart. One of the corner elements is a substantially triangular corner leg having perpendicular outside surfaces and parallel lengthwise L-shaped grooves on a 45 degree inside surface. The second element is a clamp block which includes opposite-facing L-shaped side grooves corresponding (being the mirror image thereof) to the grooves on the corner leg. The clamp block is affixed down the middle of the corner leg along the inside surface by one or more clamping fasteners such as a screw or bolt which passes through the clamp block. By turning the fastener(s), the clamp block may be loosened or removed to vertically adjust a laterally-extending panel or rail member.

1. A corner joint assembly, comprising:
 a corner leg including two parallel, longitudinally-extending, L-shaped grooves along an inside surface thereof, one on each side of a plane which bisects an apex of the leg, each corner leg groove comprising major and minor planar sidewalls with an included angle of less than 90 degrees; 
 a clamp block including two parallel, longitudinally-extending, L-shaped grooves which are opposite-facing by 180 degrees, each groove being a mirror image of an opposing one of the two corner leg grooves, each of the four said grooves being halves of two outward-facing dovetail recesses formed between the corner leg and the clamp block, a first half of each recess being in said corner leg and a second half of each recess being in said clamp block, said recesses disposed at an angle of 90 degrees; and 
 a releasable fastener for joining said clamp block to said corner leg, said clamp block having a planar base perpendicular to the direction of clamping in near abutment with an inner-facing surface of said corner leg. 
 
   
   
     2. The corner joint assembly of  claim 1  wherein said clamp block base is elongate and substantially coextensive with said corner leg. 
   
   
     3. The corner joint assembly of  claim 2  wherein said corner leg includes two perpendicular outside surfaces. 
   
   
     4. The corner joint assembly of  claim 3  wherein said inner-facing surface of said corner leg is substantially planar and is oriented at a 45 degree angle with respect to said perpendicular outside surfaces. 
   
   
     5. The corner joint assembly of  claim 4  wherein said releasable fastener is a screw. 
   
   
     6. The corner joint assembly of  claim 5  wherein said releasable fastener is a bolt. 
   
   
     7. The corner joint assembly of  claim 1  further including a rail member extending laterally from said corner leg being joined thereto by a male dovetail element captured within one of said dovetail recesses. 
   
   
     8. The corner joint of  claim 1  wherein said releasable fastener extends through the clamp block and into said corner leg. 
   
   
     9. The corner joint assembly of  claim 1  wherein the respective sidewalls of the corner leg grooves and the clamp block grooves are substantially identical in dimension. 
   
   
     10. The corner joint assembly of  claim 1  wherein said corner leg and said clamp block are composed of wood. 
   
   
     11. The corner joint assembly of  claim 1  wherein said corner leg and said clamp block are composed of metal. 
   
   
     12. The corner joint assembly of  claim 11  wherein said metal is extruded aluminum. 
   
   
     13. A corner joint assembly, comprising:
 a corner leg including only two parallel, longitudinally-extending, L-shaped grooves, each groove having major and minor planar sidewalls with an included angle of less than 90 degrees; 
 a clamp block including two opposite-facing, longitudinally-extending, L-shaped grooves, each with major and minor planar sidewalls including an angle of less than 90 degrees; 
 a releasable fastener joining said clamp block to said corner leg; and 
 wherein two pairs of the L-shaped grooves one on the clamp block and one pair on the corner leg are in opposing parallel alignment such that two dovetail recesses are formed disposed at 90 degrees from each other for forcibly receiving a closely interfitting dovetail tongue of an attached rail in each recess, each recess consisting of two halves, the first half of each recess being in said corner leg and the second half of each recess being in said clamp block. 
 
   
   
     14. The corner joint assembly of  claim 13  wherein said corner leg further includes an inner-facing surface in abutment with a planar base of said clamp block. 
   
   
     15. The corner joint assembly of  claim 14  wherein said corner leg includes two perpendicular outside surfaces. 
   
   
     16. The corner joint assembly of  claim 15  wherein said inner-facing surface of said corner leg is substantially planar and is oriented at a 45 degree angle with respect to said perpendicular outside surfaces. 
   
   
     17. The corner joint assembly of  claim 13  wherein the respective sidewalls of the corner leg grooves and the clamp block grooves are substantially identical in dimension. 
   
   
     18. A corner joint assembly, comprising:
 a corner leg including only two parallel, longitudinally-extending, L-shaped grooves, each groove having major and minor planar sidewalls with an included angle of less than 90 degrees; 
 a clamp block including only two longitudinally-extending L-shaped grooves opposite-facing by 180 degrees, each with major and minor planar sidewalls including an angle of less than 90 degrees; 
 a releasable fastener joining said clamp block to said corner leg; and 
 wherein two pairs of the L-shaped grooves one pair on the clamp block and one pair on the corner leg are in opposing parallel alignment thereby forming two dovetail recesses having outwardly convergent sidewalls are formed disposed at 90 degrees from each other for forcibly receiving a closely interfitting outwardly divergent dovetail tongue of an attached rail in each recess. 
 
   
   
     19. A corner joint assembly, comprising:
 a corner leg including two parallel, longitudinally-extending, L-shaped grooves along an inside surface thereof, one on each side of a plane which bisects an apex of the leg, each corner leg groove comprising major and minor planar sidewalls with an included angle of less than 90 degrees; 
 a clamp block including two parallel, longitudinally-extending, L-shaped grooves which are opposite-facing by 180 degrees, each groove being a mirror image of an opposing one of the two corner leg grooves, each of the four such that two outward-facing dovetail recesses are formed between the corner leg and the clamp block, the dovetail recesses being which are disposed at an angle of 90 degrees; 
 a releasable fastener for joining said clamp block to said corner leg, said clamp block having a planar base perpendicular to the direction of clamping in near abutment with an inner-facing surface of said corner leg; and 
 wherein said corner leg includes two perpendicular outside surfaces and said inner-facing surface of said corner leg is substantially planar and is oriented at a 45 degree angle with respect to said perpendicular outside surfaces.